For example, in a so-called short-pitch-type rubber track for construction machines in which plural cores are arranged at short pitches, when lugs are arranged on the outer peripheral surface of the rubber track in consideration of cut resistance or vibration reducing property, an end portion of one core among two cores adjacent to each other in the circumferential direction is likely to become a portion not covered with the lug. As a result, at the end portion of the core not covered with the lug, a covering thickness of the core covered with the rubber elastic body is thinner, which leads to a large stepwise difference in rigidity between a portion with the core and a portion without the core. Therefore, there existed a problem that, when the rubber track travels, strain is concentrated between these portions, and cracks called an edge-cutting are likely to occur at the portion corresponding to the end portion of the core of the rubber elastic body.
To solve such a problem as this, Patent Literature 1 proposes that a ridge 54 extending between lugs 53 therebefore and thereafter be formed on the outer peripheral surface of a rubber elastic body 52 so as to correspond to right and left end portions of a core 51, as exemplarily shown in FIG. 5, which relates to a developed plan view and a sectional view in the width direction on the outer peripheral surface side of the half width of a rubber track. With this technique, the ridge 54 is formed on the outer peripheral surface of the rubber elastic body 52 so as to correspond to the right and left ends of the core 51 where the edge-cuttings are most likely to occur, whereby the strain occurring at the right and left ends of the core is made dispersed, and the occurrence of cracks at the rubber elastic body 52 can be prevented.